-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Concurrent resource map
--   
--   Please see the README on GitHub at
--   <a>https://github.com/Fuuzetsu/concurrent-resource-map#readme</a>
@package concurrent-resource-map
@version 0.1.0.0

module Data.ConcurrentResourceMap

-- | A map of shared resources <tt>r</tt> keyed by <tt>k</tt>.
data ConcurrentResourceMap k r

-- | Create an empty resource map.
newResourceMap :: Ord k => IO (ConcurrentResourceMap k r)

-- | Use a resource that can be accessed concurrently via multiple threads
--   but is only initialised and destroyed on as-needed basis. If number of
--   users falls to 0, the resource is destroyed. If a new user joins and
--   resource is not available, it's created.
--   
--   Calls to <a>withSharedResource</a> can even be nested if you need
--   access to resources with different keys in the same map. Calling
--   <a>withSharedResource</a> in a nested matter on same resource key
--   should have no real adverse effects either.
withSharedResource :: Ord k => ConcurrentResourceMap k r -> k -> IO r -> (r -> IO ()) -> (r -> IO a) -> IO a